The growing of crops, including, for example, berries, in a field or other area is an activity of significant magnitude. Birds and other animals can damage crops by eating the crops and otherwise damaging the land on which the crops grow. Various types of devices and installations have been used in the past in attempts to scare birds away from crops.
It has been proposed, for example, to scare birds from a field through the use of stationary devices, such as scarecrows. The effectiveness of these devices, however, decreases after a short period of time because the birds or other animals become accustomed to the presence of the devices and lose their fear thereof.
It has also been proposed to scare birds from a field through the use of a loud noise. Such a loud noise may be produced by acoustic systems, such as recordings of distress and warning calls of the species sought to be repelled, or an air gun that ignites combustible gas at predetermined intervals. After a period of use of loud noises, however, birds become accustomed to the noise and the scaring effect is diminished.
It has also been proposed to protect crops and fields against birds through the use of nets or other protective webbing. Use of this method, however, is limited due to the prohibitive cost of building and maintaining such a system, especially over large plots of land.
Because of the problems associated with the use of stationary devices, loud noises, and netting systems to deter birds and other animals from crop fields, farmers have attempted to employ the use of repelling systems for protection. Such systems have included devices that carry scarecrows or other deterrent objects, and can move them in a predetermined motion. The disadvantage of these types of systems, however, is the same as that of stationary devices and loud noises. That is, after a time the birds or animals to be repelled become accustomed to the presence of the scaring device and the scaring effect is diminished.
Therefore, it is desirable to provide a system to repel birds and other animals that overcomes the disadvantages of the prior art.